Add Publisher v2 + 5 extracted skills

Publisher fixes:
- Checkout new branch before push (was pushing main ref)
- Verify files staged before commit
- Handle duplicate files gracefully
- Clean error reporting per stage

Skills merged to main:
- mcp-server-setup (from pipeshub-ai)
- research-pipeline (from Blacknode)
- multi-agent-sequential-workflow (from Fast-LLM-Agent-MCP)
- unifai-workflow-execution (from UnifAI)
- code-review-agent-workflow (from AgentKit)

skills/multi-agent-sequential-workflow/examples.md

@@ -0,0 +1,10 @@
+# Examples: multi-agent-sequential-workflow
+
+## Usage Example
+
+```python
+# How to use this skill
+# Inputs: User query with location
+# Process: Step 1: Researcher agent (agent.py) uses LangGraph create_react_agent with BedrockModel to gather raw facts about the destination. → Step 2: Travel Guide Generator agent (agent.py) synthesizes the gathered data into a structured travel guide based on the user's request and raw information provided by the researcher. → Step 3: Writer agent (agent.py) formats the final response, including the structured guide content and prominently features the 'Suggested Web Pages' section.
+# Outputs: Structured travel guide with key sections, Final client response
+```